Vinylphosphinimines and a method of preparation



United States Patent 3,452,080 VINYLPHOSPHINIMINES AND A METHOD OF PREPARATION George R. Harvey, Kirkwood, and Kenneth Wayne Ratts, Creve Coeur, Mo., assignors to Monsanto Company,

St. Louis, Mo., a corporation of Delaware No Drawing. Filed Dec. 29, 1965, Ser. No. 517,474 Int. Cl. C07f 9/02 U.S. Cl. 260-471 9 Claims ABSTRACT OF THE DISCLOSURE Vinylphosphinimines of the formula RI C lHz R O R,P=N t'-l 1t wherein R is selected from the group consisting of alkyl having up to 12 carbon atoms and phenyl; R is selected from the group consisting of hydrogen, alkyl having up to 4 carbon atoms and phenyl; R" is selected from the group consisting of hydrogen, alkyl having up to 4 carbon atoms, phenyl and benzyl; and R is selected from the group Consisting of alkyl having up to 12 carbon atoms, alkoxy having up to 12 carbon atoms, amino, monoand dialkylamino having up to four carbon atoms in each alkyl moiety, aromatic radicals selected from the group consisting of phenyl, phenoxy, benzyl, benzoxy and said aromatic radicals containing substituents selected from the class consisting of alkyl having up to four carbon atoms, chlorine, bromine and nitro; prepared by the reaction in a chlorinated hydrocarbon of the appropriate fl-azido compound with the appropriate phosphine.

These compounds have phytotoxic properties.

This invention relates to a novel process by which new and useful compounds can be formed. By the reaction of a class of vinyl azides with phosphines, compounds with useful ph-ytotoxic properties can be produced. These compounds are useful in inhibiting the growth of noxious vegetation.

The vinyl azides useful in practicing this invention are described and claimed in copending application Ser. No. 517,488, filed Dec. 29, 1965, by George R. Harvey.

The novel reaction takes place in accordance with the equation:

wherein R is selected from the class consisting of alkyl of up to twelve carbon atoms and phenyl; wherein R is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms, and phenyl; wherein R" is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms, phenyl and benzyl; and wherein R is selected from the class consisting of alkyl of up to twelve carbon atoms, alkoxy of up to twelve carbon atoms, amino, monoalkylamino having up to four carbon atoms in the alkyl moiety, dialkylamino having up to four carbon atoms in each alkyl moiety, the aromatic radicals of the class consisting of phenyl, phenoxy, benzyl, benzoxy and the said aromatic radicals containing substituents selected from the class consisting of alkyl of up to four carbon atoms, chlorine, bromine and nitro.

This novel reaction is conducted in a chlorinated hydrocarbon solution and preferably in a solvent of lowboiling point, such as chloroform, methylene chloride, carbon tetrachloride or ethylene dichloride. Low to moderate temperatures (about 20 C. to 40 C.) may be used so as to avoid a too vigorous reaction. The reaction evolves nitrogen and can be continued until the reaction is completed and the nitrogen evolution subsides.

The desired products may be separated in crystalline form by diluting the reaction mixture with aliphatic h-ydrocarbons such as pentane, hexane and heptane. Sufficient of the aliphatic hydrocarbon should be added to induce turbidity. The mixture may be filtered after cooling and the precipitate further purified by recrystallization from a mixture of the described chlorinated hydrocarbons and the aliphatic hydrocarbons.

Further details of the preparation of the new com pounds are set forth in the following examples.

Example 1 Example 2 The procedure of Example 1 was repeated except that triphenylphosphine was reacted with ethyl fi-azido-amethylcrotonate. The resulting product was identified as ethyl 13- (triphenylphosphinimino -u-methylcrotonate.

Example 3 The procedure of Example 1 was repeated using tri-nbutylphosphine in place of triphenylphosphine. The resulting product was ethyl ,B-(tri-n-butylphosphinimino) crotonate.

Example 4 The reaction of triphenylphosphine and ,B-azido-crotonamide conducted in accordance with the general procedure of Example 1 resulted in a compound identified as 8-(triphenylphosphinimino)crotonamide.

Example 5 N,N-diethyl 3-azido-2-methylcrotonamide was reacted with triphenylphosphine by disolving the reactant in chloroform at 35 C. The product separated from the reaction mixture was identified as N,N-diethyl-,B-(triphenylphosphinimino -u-methylcrotonamide.

Example 6 Ethyl ,G-azido-phenyl was reacted with triphenylphosphine by the procedure of Example 1 whereby a product was produced having the formula Example 7 The reaction of tri(n-butyl)phosphine with nitrophenyl B-azidocrotonate by the general procedure of Example 1 resulted in the formation of p-nitrophenyl fi-(tri-n-butylphosphinimino) crotonate.

Example 8 a-Phenyl-B-azidocrotonamide was reacted with triphenylphosphine by the procedure of Example 1. The product separated from the reaction mixture was identified as 8- (triphenylphosphinimino)-a-phenylcrotonamide.

Example 9 The reaction of 4-chloropheny1 B-azidocrotonate with triphenylphosphine in accordance with the procedure of Example 1 produced p-chlorophenyl B-(triphenylphosphinimino) crotonate.

Example 10 Triethylphosphine was reacted by the procedure of Example 1 with p-chlorobenzyl fi-azidocrotonate to pro duce p-chlorophenyl p (triethylphosphinimino)crotonate.

Example 11 Triphenylphosphine was reacted with p-ethylphenyl fl-azidocrotonate by the procedure of Example 1 to produce p-ethylphenyl 13 (triphenylphosphinimino)crotonate.

Example 12 By the procedure of Example 1 tri-n-butylphosphine was reacted with 3,4-d-ibromophenyl fl-azidocrotonate whereby 3,4- dibromophenyl B (tri-n-butylphosphinimino) crotonate was formed.

Example 13 Using the procedure of Example 1 and reacting triphenylphosphine with fi-azido oa-phenylcrotonamide, a compound identified as B-triphenylphosphinimino a-phenylcrotonamide was produced.

Example 14 By the procedure of Example 1, ,B-azido Z-methylvinyl benzyl ketone was reacted with triphenylphosphine. A compound of the following formula was produced:

0 P=N-( 3=GHz( iCHi Following the procedure of Example 1, triethylphos- RI Bib R" (H) R31==No=( J-c-R'" wherein R is selected from the class consisting of alkyl having up to twelve carbon atoms and phenyl; wherein R is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms and phenyl; wherein R" is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms, phenyl and benzyl; and wherein R'" is selected from the class consisting of alkyl of up to twelve carbon atoms, alkoxy of up to twelve carbon atoms, amino, monoalkylamino having up to four carbon atoms in the alkyl moiety, dialkylamino having up to four carbon atoms in each alkyl moiety, the aromatic radicals selected from the class consisting of benzyl, benzoxy, phenyl, phenoxy and the said aromatic radicals containing substituents selected from the class consisting of alkyl of up to four carbon atoms, chlorine, bromine and nitro.

2. A compound defined by claim 1 wherein R is phenyl, R and R" are hydrogen, and R is ethoxy.

3. A compound defined by claim 1 wherein R is phenyl, R is hydrogen, R" is methyl and R' is ethoxy.

4. A compound defined by claim 1 wherein R is phenyl, R' and R" are each hydrogen, and R is amino.

5. A compound defined by claim 1 wherein R is phenyl, R is hydrogen, R" is methyl and R' is amino.

6. A method of preparing a compound of the formula wherein R is selected from the class consisting of alkyl having up to twelve carbon atoms and phenyl; wherein R is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms and phenyl; wherein R is selected from the class consisting of hydrogen, alkyl of up to four carbon atoms, phenyl and benzyl; and wherein R' is selected from the class consisting of alkyl of up to twelve carbon atoms, alkoxy of up to twelve carbon atoms, amino, monoalkylamino having up to four carbon atoms in the alkyl moiety, dialkylamino having up to four carbon atoms in each alkyl moiety, the aromatic radicals selected from the class consisting of benzyl, benzoxy, phenyl, phenoxy and the said aromatic radicals containing substituents selected from the class consisting of alkyl of up to four carbon atoms, chlorine, bromine and nitro; which comprises reacting in a chlorinated hydrocarbon solvent a compound of the formula 7. A method defined by claim 6 wherein R is phenyl, R and R" are each hydrogen, and R'" is ethoxy.

8. A method defined by claim 6 wherein R is phenyl, R is hydrogen, R" is methyl, and R is ethoxy.

9. A method defined by claim 6 wherein R is phenyl, R and R are each hydrogen, and R is amino.

References Cited Journal of Organic Chemistry, by Leifier et al., vol. 28 (April 1963), QD24156, pp. 902-906 relied on.

LORRAINE A. WEINBERGER, Primary Examiner.

L. A. 'I'HAXTON, Assistant Examiner.

US. Cl. X.R. 

